2000-06-13 Kaz Kylheku <kaz@ashi.footprints.net>
A few optimizations. Got rid of unnecessary wakeups of timer threads,
tightened up some critical regions and micro-optimized some list
manipulation code.
* sysdeps/pthread/timer_routines.c (__timer_thread_queue_timer):
Returns int value now to indicate whether timer was queued at head.
* sysdeps/pthread/posix-timer.h: Likewise.
* sysdeps/pthread/timer_settime.c (timer_settime): Takes advantage of
new return value from __timer_thread_queue_timer to avoid waking
up timer thread unnecessarily.
* sysdeps/pthread/posix-timer.h (timer_id2ptr): No longer checks
inuse flag, because this requires mutex to be held. Callers updated
to do the check when they have the mutex.
* sysdeps/pthread/timer_getoverr.c: Add check for inuse here.
* sysdeps/pthread/timer_settime.c (timer_settime): Tighter critical
regions: avoids making system calls while holding timer mutex, and
a few computations were moved outside of the mutex as well.
* sysdeps/pthread/timer_gettime.c (timer_gettime): Likewise.
* sysdeps/pthread/posix-timer.h (list_unlink_ip): Function name changed
to list_unlink_ip, meaning idempotent. Pointer manipulation
changed to get better better code out of gcc.
* sysdeps/pthread/timer_routines.c (list_unlink): Non-idempotent
version of list_unlink added here.
* sysdeps/pthread/timer_delete.c: Use appropriate list unlink
function in all places: idempotent one for timers, non-idempotent
one for thread nodes.
* sysdeps/pthread/timer_settime: Likewise.
* sysdeps/pthread/timer_routines.c: Likewise.
